# JUnit5 `@RepeatedTest`注解示例 > 原文： [https://howtodoinjava.com/junit5/repeated-test-annotation-example/](https://howtodoinjava.com/junit5/repeated-test-annotation-example/) 通过 JUnit5 [`@RepeatedTest`](http://junit.org/junit5/docs/current/api/org/junit/jupiter/api/RepeatedTest.html)注解，可以编写可以多次运行的**可重复测试模板**。 频率可以配置为`@RepeatedTest`注解的参数。 ## 1\. `@RepeatedTest`注解用法 要创建可重复的测试模板方法，请使用`@RepeatedTest`注解该方法。 ```java @DisplayName("Add operation test") @RepeatedTest(5) void addNumber(TestInfo testInfo) { Calculator calculator = new Calculator(); Assertions.assertEquals(2, calculator.add(1, 1), "1 + 1 should equal 2"); } ``` 在上面的代码中，`addNumber()`测试将重复 5 次。 请注意，每次重复测试的行为**都类似于常规`@Test`方法的执行，并且完全支持相同的生命周期回调和扩展**。 这意味着对于每个单独的调用，将在适合它们的测试生命周期的地方调用[`@BeforeEach`](//howtodoinjava.com/junit-5/before-each-annotation-example/)和`@AfterEach`带注解的方法。 ```java package com.howtodoinjava.junit5.examples; import org.junit.jupiter.api.AfterAll; import org.junit.jupiter.api.AfterEach; import org.junit.jupiter.api.Assertions; import org.junit.jupiter.api.BeforeAll; import org.junit.jupiter.api.BeforeEach; import org.junit.jupiter.api.DisplayName; import org.junit.jupiter.api.RepeatedTest; import org.junit.jupiter.api.RepetitionInfo; import org.junit.jupiter.api.Test; import org.junit.jupiter.api.TestInfo; import org.junit.platform.runner.JUnitPlatform; import org.junit.runner.RunWith; @RunWith(JUnitPlatform.class) public class RepeatedTestExample { @BeforeAll public static void init(){ System.out.println("Before All init() method called"); } @BeforeEach public void initEach(){ System.out.println("Before Each initEach() method called"); } @DisplayName("Add operation test") @RepeatedTest(5) void addNumber(TestInfo testInfo, RepetitionInfo repetitionInfo) { System.out.println("Running addNumber test -> " + repetitionInfo.getCurrentRepetition()); Assertions.assertEquals(2, Calculator.add(1, 1), "1 + 1 should equal 2"); } @AfterEach public void cleanUpEach(){ System.out.println("After Each cleanUpEach() method called"); } @AfterAll public static void cleanUp(){ System.out.println("After All cleanUp() method called"); } } ``` 上面程序的输出： ```java Before All init() method called Before Each initEach() method called After Each cleanUpEach() method called Before Each initEach() method called Running addNumber test -> 1 After Each cleanUpEach() method called Before Each initEach() method called Running addNumber test -> 2 After Each cleanUpEach() method called Before Each initEach() method called Running addNumber test -> 3 After Each cleanUpEach() method called Before Each initEach() method called Running addNumber test -> 4 After Each cleanUpEach() method called Before Each initEach() method called Running addNumber test -> 5 After Each cleanUpEach() method called After All cleanUp() method called ``` ## 2\. 自定义显示测试名称 除了指定重复次数之外，您还可以**为每个重复**指定自定义显示名称。 此自定义显示名称可以是*静态文本+动态占位符*的组合。 当前，支持 3 个占位符： * `{displayName}`：`@RepeatedTest`方法的显示名称。 * `{currentRepetition}`：当前重复计数。 * `{totalRepetitions}`：重复总数。 ```java @RunWith(JUnitPlatform.class) public class JUnit5AnnotationsExample { @DisplayName("Add operation test") @RepeatedTest(value = 5, name = "{displayName} - repetition {currentRepetition} of {totalRepetitions}") void addNumber(TestInfo testInfo) { Assertions.assertEquals(2, Calculator.add(1, 1), "1 + 1 should equal 2"); } } ``` 运行以上测试将在下面输出：  JUnit5 重复测试的显示名称 您可以使用两种预定义格式之一，即`RepeatedTest.LONG_DISPLAY_NAME`和`RepeatedTest.SHORT_DISPLAY_NAME`。 如果未指定，则`SHORT_DISPLAY_NAME`是默认格式。 * `RepeatedTest.LONG_DISPLAY_NAME` – `{displayName} :: repetition {currentRepetition} of {totalRepetitions}` * `RepeatedTest.SHORT_DISPLAY_NAME` – `repetition {currentRepetition} of {totalRepetitions}` ```java @DisplayName("Add operation test") @RepeatedTest(value = 5, name = RepeatedTest.LONG_DISPLAY_NAME) void addNumber(TestInfo testInfo) { Assertions.assertEquals(2, Calculator .add(1, 1), "1 + 1 should equal 2"); } ``` ## 3\. `RepetitionInfo`接口 [`RepetitionInfo`](http://junit.org/junit5/docs/current/api/org/junit/jupiter/api/RepetitionInfo.html)用于将有关重复测试的当前重复的信息注入`@RepeatedTest`，`@BeforeEach`和`@AfterEach`方法中。 ```java @RunWith(JUnitPlatform.class) public class JUnit5AnnotationsExample { @BeforeEach public void initEach(RepetitionInfo info){ int currentRepetition = info.getCurrentRepetition(); int totalRepetitions = info.getTotalRepetitions(); //Use information as needed } @DisplayName("Add operation test") @RepeatedTest(value = 5, name="{displayName} :: repetition {currentRepetition} of {totalRepetitions}") void addNumber(TestInfo testInfo) { Calculator calculator = new Calculator(); Assertions.assertEquals(2, calculator.add(1, 1), "1 + 1 should equal 2"); } @AfterEach public void cleanUpEach(RepetitionInfo info){ int currentRepetition = info.getCurrentRepetition(); int totalRepetitions = info.getTotalRepetitions(); //Use information as needed } } ``` 将我的问题放在评论部分。 学习愉快！ [源码下载](https://github.com/lokeshgupta1981/Junit5Examples/tree/master/JUnit5Examples)